Char from lauan pyrolysis was used as feedstock, and its structure and surface properties were improved through physical and chemical activation way with microwave-assisted method and the traditional calcination method. After being activated, the biochar was characterized by various characterization techniques, including nitrogen adsorption, scanning electron microscope, X-ray diffraction, thermogravimetric analysis and Fourier transform infrared spectroscopy. The results showed that the activated biochar had abundant micropores and mesopores which formed a multilevel pore structure, and the surface area of the micropores accounted for 36%~48%. In addition, the biochar activated through microwave pretreatment and N2 atmosphere calcination had a high surface area of 1224m2/g. The uniform microwave heating produced micropores and the mesopores were further formed through calcination. The efficient synergistic effect of both the two thermal treatments led to the high surface area and multilevel pore structure. The activated biochar yield of 42% was obtained under the condition of microwave pretreatment and N2 calcination. Besides, different activation methods had a significant effect on the infrared properties of biochar, and the oxygen-containing groups on the surface of activated biochar were greatly reduced. The thermal stability of biochar after activation was significantly improved and there were no apparent weight loss peaks, which was beneficial for the utilization of biochar as catalyst support.